29.5.2023

Kemijoki – Major construction project for pumped storage hydropower plants that enable safe energy transition

We are advising Kemijoki Oy as the company is exploring the possibility of building pumped storage hydropower plants as part of its existing production infrastructure in Northern Finland.

The socially significant project enables safe energy transition and would have a significant role in mitigating climate change.

The 200–600 MW pumped storage power plants explored by Kemijoki Oy would increase the regulating capacity of hydropower in Finland by up to 4,000 MW. The increase is exceptionally significant since Finland’s current hydropower capacity, which is mainly regulatable, is 3,100 MW. The scale of the project is also reflected in the fact that the nominal capacity of the company’s largest operating hydropower plant, Petäjäskoski hydropower plant, is 182 MW. The scale of the possible investment totals up to 3 billion euros.

The production of weather-dependent wind and solar power will increase significantly in Finland. This requires ensuring sufficient production capacity that can be regulated, and hydropower is the most important form of such production.

The overall generating capacity of pumped storage hydropower is on the rise in Europe and elsewhere in the world, reducing the need of fossil fuels. The pumped storage plant consists of two reservoirs that will help the plant to produce power when demand is high by running water through turbines down from the upper reservoir to the lower reservoir. When demand for electricity is low, the pumped storage plant will pump water back up into the upper reservoir.

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